Steam-engine.



No. 665,235. Patented Ian. I, 190i.

. H. LENTZ.

STEAM ENGINE.

(Application filed Nov. 9, 1898.)

(No Model.)

HUGO LENTZ, OF BET INN, AUSTRIA-HUNGARY.

STEAM-*ENGINE.

SPECIFICATION forming part of Letters Patent No. 665,235, dated January 1, 1901.

Application filed November 9, 1898. Serial No. 695,943. (No model.)

To all whom, it may concern:

Be it known that I, HUGO LENTZ, a citizen of the United States, residing at Briinn, Aus tria-Hungary, have invented certain new and useful Improvements in Steam-Engines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to a novel construction in a steam-engine, the object being to provide a very cheap, simple, and efficient device of this character of the compound type; and it consists in the features of construction and combinations of parts hereinafter fully described and claimed.

In the accompanying drawings, illustrating my invention, Figure 1 is a central vertical longitudinal section of a steam-engine constructed in accordance with my invention, taken on the line 1 1 of Fig. 2. Fig. 2 is a horizontal section of same on the line 2 2 of Fig. 1. Fig. 3 is a transverse section of same on the line 3 3 of Fig. 2.

Referring now to said drawings, A indicates the cylinder, which is contracted at its forward end B. The differential piston moves in said cylinder A and contracted end B and consists of a cylinder which is open at its for ward end, through which the pitman D enters, which is pivotally connected with said piston in a usual and well-known manner. Said pitman D is connected at its other end with the crank l of the crank-shaft 2. Said crank 1 moves in a casing 3, in which said cylinder A terminates and which forms an exhaust-chamber from which steam is exhausted through the exhaust-pipe 4.

The head E of piston 0 moves in the large end of the cylinder A and divides the latter into two chambers 5 and 6, said chamber 5 being ring-shaped and forming the high-pressure chamber, and chamber 6 circular and of practically twice the cross-sectional area of chamber 5 and forming the lo w-pressure chamber. Said piston-head E is provided with an opening 7, connecting the chambers 5 and 6, and with an opening 8, connecting the chamber 6 with the interior of said piston C. Said openings are controlled by a slide-valve 9, moving in a guide 10 on said head E and connected at its middle portion with an extension 11 of the pitman D, which passes through said opening 8 and enters an opening 12 in said valve 9. Steam enters a chamber 13 below the contracted portion B of cylinder A and thence enters the valve-chamber 11, in which the valve 15 moves and which controls the inlet-port 16 into the chamber 5 of cylinder A. Said valve 15 is operated from an eccentric 17 on shaft 2 in an obvious manner. When said piston O has reached the forward limit of its stroke, as shown in Fig. 2, said valve 15 has uncovered port 16 and steam is admitted to chamber 5. In this position of the piston the valve 9 will obviously be in the same position as when said piston reaches the rearward limit of its stroke, as shown in Fig. 1, thus closing both openings 7 and 8 in said piston-head E. The admission of steam will obviously force said piston toward the rearward limit of its movement, turning the crank lin the direction indicated by the arrow. This movement of the piston U obviously causes a transverse movement of said valve 9 in a direction to uncover the exhaust-port 8, through which the steam in chamber 6 is exhausted, such exhaust-port 8 remaining open and the passage 7 remaining closed during the entire rearward stroke of the piston. The valve 15 can be set to cutoff the steam-supply at any point in the rearward stroke. Upon the beginning of the return stroke of the piston the valve 9 uncovers the opening 7, whereupon the steam expands and rushes into the chamber 6, thus forcing the piston upon its return stroke,owing to the differential cross-sectional areasof said chambers 5 and 6, as will be apparent. Near the end of the return stroke of the piston the passage 7 is again closed, and

upon the beginning of the next stroke the port 8 is again opened, as is likewise the valve 15. In this'manner I obviously produce an extremely simple and efficient compound engine which has also the advantage that it can be readily converted into a full-pressure engine.

To convert said engine into a full-pressure, the valve 15 is entirely removed. The action of the valve 9 remains exactly the same and entirely controls the engine, the sole difference in operation residing in the fact that in running the engine as a compound the return stroke is effected by expansion only,

while running as a full-pressure engine full pressure is obtained both ways.

My engine is very eficient either as a fullpressure or compound and its simplicity and the total absence of all complicated valve mechanism make it cheap and durable. By means of the casing 3 all vital parts are thoroughly protected, and by partially filling said casing with oil, together with the condensed steam remaining therein, the pitinan can also be made to serve as a lubricating member, thus enabling me to dispense with oil-cups to a large extent.

I claim as my invention- 1. A steam-engine having a cylinder, a trunk-piston moving therein and carrying an annularly-enlarged head dividing said cylinder into two differential chambers, a steaminlet port in the smaller of said chambers, a passage in the enlarged portion of said piston-head forming the connection between said differential chambers, an exhaust-port in said piston-head, a single valve controlling said exhaust-port and said passage, and means for operating said valve.

2. A differential compound steam-engine having a cylinder, a trunk-piston moving therein and carrying an annularly-enlarged head dividing said cylinder into two difierential chambers, one of said chambers forming the high-pressure and the other the lowpressure chamber, a steam-inlet valve in said high-pressure chamber, a passage in the enlarged portion of said piston-head forming the connection between said high and low pressure chambers, an exhaust-port in said piston-head, a single valve common to said exhaust-port and said passage, and means for operating said valve.

3. In a steam-engine, a cylinder contracted at its forward end, a differential piston movable in said cylinder and having a head adapted to divide the larger end of said cylinder into two respectively high and low pressure chambers, an opening in said pistonhead establishing communication between said high and low pressure chambers, an exhaust-port in said piston-head, a slide-valve in said piston-head common to both said openings and movable transversely to the direc tion of motion of said piston, a pitman pivotally connected with said piston, and an extension on said pitman connected with said valve and adapted to operate the same, substantially as described.

4. In a steam-engine, a cylinder contracted at its forward end, a hollow cylindrical piston movable in said contracted end of said cylinder and provided with an enlarged head movable in the larger end of said cylinder and adapted to divide the same into high and low pressure chambers respectively, an opening in said piston-head establishing communication between said high and low pressure chambers, an exhaust-opening in said pistonhead establishing communication between said low-pressure chamber and the interior of said piston, a slide-valve common to both said openings and movable transversely to the direction of motion of said piston, and a pitman pivotally connected between its ends with said piston and at one end with said slidevalve to operate the latter, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

HUGO LENTZ.

Witnesses:

WILHELM V011, MORITZ SCHMOLLING. 

